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Topic: The 2017 melting season (Read 566957 times)

What's notable about this system is how long it's forecasted to linger in the same vicinity. As mentioned, the Laptev Sea looks to see most of the action. Considering the ice-free expanses in the Laptev and the fractured nature of the pack extending well into the CAB, i can't help but think that we'll see some serious waves from all of this.

Below is a surface wind gfs forecast starting in 2 days and ending in 5 days.

absolutely. someone was referring to a bias to the low side in polls in this forum but i'm quite convinced that this year we shall see events "muy grave" or "strong tobacco" as we say where i come from LOL

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...On the other hand, the forecasted cyclone this month isn't surrounded by any strong high pressure systems. There's weak low pressure system over Scandinavia, pretty neutral pressures over Greenland and a shallow high pressure over the Beaufort sea.This type of set up is very unlikely to cause much damage, it might in fact be better for ice preservation as it's carrying somewhat cool air and more cloud over the central pack.

I agree. Predictions show, aside to the cooling storm, a warmer air tongue from Asia, but nothing out of the ordinary, and in any case, this is already the middle of June. The continent is relatively cold.Nevertheless, the advance of the "gruyere holes", these immense open-water spaces in the Arctic ice pack, is very disturbing. These holes have a very sharp edge, and where the edge is not so clean cut, ice shows an image of broken blocks reaching the level of amalgam. I wonder if the relative low thickness and youngness of the ice pack is helping to promote these holes more than our eyes can see.If it were not for this, I would assume a rebound, but these open spaces are simply huge and everywhere, one at least per sea: Beaufort , Chuckchi, ES, Laptev, and Kara Seas. Isn't this unprecedented?

Nevertheless, the advance of the "gruyere holes", these immense open-water spaces in the Arctic ice pack, is very disturbing. These holes have a very sharp edge, and where the edge is not so clean cut, ice shows an image of broken blocks reaching the level of amalgam. I wonder if the relative low thickness and youngness of the ice pack is helping to promote these holes more than our eyes can see.If it were not for this, I would assume a rebound, but these open spaces are simply huge and everywhere, one at least per sea: Beaufort , Chuckchi, ES, Laptev, and Kara Seas. Isn't this unprecedented?

ECMWF 12z Op run has a GAC by D8-D9!! 971 hpa bomb cyclone right over the central CAB! While it's too early to make any conclusions from this forecast as it's so far ahead in time, we clearly need to watch the coming forecasts very closely.

But before we are there we need to handle a 4 DAY long Moderate PAC bottoming out t 978 hpa!! The first cyclone seems to be more certain to linger over the area for 2-3 days with a SLP below 980 hpa.

And we will initially have a decent ice transport through Fram from our first cyclone by D3-D4!

Normally, two such strong cyclones in June shouldn't render too much damage but the situation in the Arctic isn't normal anymore. The Laptev hole should widen during the next couple of days as the wind will do its job.

Please, don't get too excited about things beyond 6 days out. This is a forum, not a news paper.

And I believe that a moniker like GAC is given après le fait. Besides, it would be the third in 5 years. It's almost becoming normal.

For now, we have the dipole and a medium cyclone forecast for the next couple of days. It will be interesting to see what that does.

The weather 48-96 hours out could be significant with that storm in a tight loop on the north of the Laptev. 2M temperatures could be significant as well, with Siberian temps in the mid 20s and higher swept north, which will reduce snow cover on land and potentially on ice.

Ice in the Kara may get swept back over open water, and more CAB ice shoved towards the exit along the Barentsz.

Yes, it will be interesting enough already, I expect, without looking further.

It is indeed surprising that despite the large land snow anomaly (cool continents) and despite the low melting pond index (Schroeder et al in Neven's latest ASIB post) that 2017 continues its tracks among the lowest years in SIE (IJIS/JAXA).

Is the record low PIOMAS volume making its mark ?

I tend to think that lack of volume cannot manifest itself this early in the melting season, and thus that it is something else. Neven posted (June 4) on the ASIB :

This is the worst kind of set-up imaginable, especially at this time of year.

regarding the positioning of high pressure over the Beaufort, kicking the Beaufort Gyre in motion.And indeed it seems that over the past two weeks that Gyre has been spinning nicely and caused significant compaction on the Pacific side of the Arctic, and export through Fram on the Atlantic side.

And with the (weak) dipole that is still in place, and the lack of cloud cover over the Arctic in general, it seems to me that June 2017 so far has been very conducive to melt/compaction leading to the losses in SIE that cannot be explained by the lack of melting potential. In fact, despite the onset of melt in some places, the Arctic is still looking pretty 'white' overallhttps://lance3.modaps.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2017166.terra.4kmEspecially compared to prior years.

I think that once the weather turns, we should really be seeing a slowdown of what seems to be a relentless drive to the bottom so far. Most indicators (except for PIOMAS) still suggests that 2017 will slow down and end higher.

It's of course possible the islands on seas bordering the CAB generate vortixes in the Ocean, the same way as they do it in the atmosphere, and let the halocline break on the already open locations. Thus the fresh water from Siberian melt would reach the CAB less efficiently and help in the later melt during summer. But I won't change my vote, as it is already closed, and imho this isn't yet the total melt year.

The circulation around low pressure systems entering around the Laptev is driving the cold from the residual snow into the Kara and Barents Seas where it can't do much good. Over the next week on climate reanalyser those seas are consistently below freezing whereas the rest of the Arctic will see above freezing temperatures

I think that once the weather turns, we should really be seeing a slowdown of what seems to be a relentless drive to the bottom so far. Most indicators (except for PIOMAS) still suggests that 2017 will slow down and end higher.

2017 still have higher than average SIE in Barents and Kara,but this ice will melt out anyway in upcoming weeks. The Hudson bay will also melt earlier than 2016\12\07. I expect the total SIE will drop faster than previous years in next weeks

slow wing "What do more experienced ice watchers than me have to say on the gif?" not sure i qualify but the mslp over the whole arctic has dropped and whatever is taking place above the surface there's a huge surge of water into the arctic below, following the path of least resistance. I'm looking mainly at the Atlantic side, and expect warming/melt to show wherever that influx flows. Not just from the influx but from the consequent turbulence. So my guess is any Atlantic water is heading for Laptev via St Anna trough.

Here's a comparison of SST anomalies for June 15th 2012 (left), 2016 (middle) and 2017 (right).

2017 is more similar to 2016 than 2012, especially on the Pacific side, but is also warming up more and more on the Atlantic side. I would expect more 'heat' in the Beaufort hole, but the colours can fluctuate somewhat from day to day (for instance, the red at the top, in the Bering Strait and Sea, was more conspicuous yesterday and the day before).

I believe that sea surface temperature (or ocean heat flux to be more precise) was one of the reasons 2016 still ended up as low as it did. Maybe this will play a role again this year. Or perhaps it already does, which explains why SIE keeps going down steadily, even though there is relatively little preconditioning (like Rob says). But I think the Beaufort Gyre plays a role as well.

One big question I have: Will a slow/late melt of the periphery (Barents, for instance) still protect the core? One would think that if ice is as thin as PIOMAS says, we get more holes within the pack, and with cyclone dominance, massive divergence (like we saw last year).

But, anyway, here is the DMI SSTa comparison. I'll post another one as soon as images in my archive line up again (I didn't use to download these maps very often, except for ASI updates):

...One big question I have: Will a slow/late melt of the periphery (Barents, for instance) still protect the core? One would think that if ice is as thin as PIOMAS says, we get more holes within the pack, and with cyclone dominance, massive divergence (like we saw last year)....

The answer is, IMO, "possible if things happen in a way which would allow it to do so". 1st, depends on which side the core would end up being melt from the most, and we can't know that months in advance (not this season, i mean, with slow Atlantic side, you know). 2nd, depends on whether such parts of periphery would survive long enough to provide such protection by the time most intensive core melting would be going on. I bet there is much more uncertainty than two things i mentioned, too.

As for holes, even that could somewhat be helped "from the periphery" with "right" winds compacting ice and thus closing (at least some) such holes with the help of some "formerly periphery" ice. Perhaps it'd be only some very small help, but still, can happen.

seaicesailor

The loss of snow in the last days has been swift and major, as others anticipated, and Laptev sea fast ice shows some areas in a really bad state. The cyclone is going to further destroy the drift ice in Laptev, but no doubt it is going to put a brake on this belated June momentum... interesting. Because the 850 hPa anomalies of 10 to 15 of June were pretty high.OTOH the last run does not show such centered final GAC (which I think it would have really halted the melting season) but a weaker, persisting cyclone that stays close to the coasts of Asia, allowing (or even strengthening) for the general circulation Pacific-> Atlantic that has been displacing the ice pack gradually since March.Now will the Arctic get the "2013 syndrome"?

And now for something totally superficial . . . Is there ever going to be an inflection point in 2017 extent?

It looks so smooth, the term permanent inflection comes to mind. More or less equally thin ice together with an average melting season without extremes until now, gives that smooth ride down to - well, down to where? ...

Those, who hope/ wish for a 2013/ 14 Rebound are pretty much so focused on a graph, and one or the other Aspect, that they miss the whole Picture.With current Jetstream Dynamics and Extreme Weather Frequency there is NO WAY, that we're heading for a Rebound.Last Season, a so- called "average" Melt Season ended up with 2nd lowest Extent and 2nd lowest Volume. Storms, Export and mechanic Stress are gonna be the Storyof this Season.If the coming Solstice coupled up with Peak Insolation & Meltwater River Runoff could provide a huge Momentum for further Melt. Next 2- 3 weeks will be crucial.

The state of the ice north of Greenland catches the eye. Wipneus cranks up the contrast for those gifs in order to pick out features, so how bad and/or unusual is the situation there?

Looking on Worldview, I was surprised to see the amount of year-to-year variation in that area.

Hoping this 7.7 Mb gif loads so you can see what I mean.

The year is displayed in the top right hand corner.

I score it:2014 worst2013 second worst2012 ~ 20172015 and 2016 the ice looks in good shape.

In any event, 2017 doesn't stand out as anomalous. Apparently there are 'good years' and 'bad years' for the sea ice at this particular date and area.

What do more experienced ice watchers than me have to say on the gif?

unfortunately i lack the right words but IMO the image quality is not comparable, you can see that in one and the same image there is a straight artificial "border beyond which the ice looks homogeneous while on the right of that "border" the ice looks different. to me that means that either resulution or other factors like clouds and corrections have their impact which spoil the picture to the point a comparison becomes useless.

the ice this year is by no means in good shape and has not been in bad shape in 2014, 2014 was the year when many claimed a recovery because the ice recovered from mid 2013 till 2015.

those are known facts, perhaps put a bit simple and those images contradict those facts which again means for me they are not suitable to compare the state of the ice on a year to year basis and are misleading.

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Happening now over Laptev Sea up to: 50km/h winds, 2.5C temps, and quite a bit of precipitable water (26.500 kg/m2) in the air column - could be raining as we speak?

A number of us had been looking ahead to this moment for several days. If 2M temps are in the 2-3C range, it is very probably rain falling. The 850mb temps are similar or slightly higher, so I think parts of the Laptev are currently getting a shower.

Oh yes, rain has been falling over this part of Siberia. In accordance to that, the snow cover has shrunk and the areal extension has gone down since yesterday which is clearly seen at EOSDIS worldview from NASA.

Let's try it again! BOTH GFS and ECMWF 12z op runs depicts a possible bomb cyclone by D8 ranging from 961 hpa (GFS) to 971 hpa (ECMWF). While it certainly is far away in time to make any clear conclusions it is absolutely a bad omen that both models evolve such a strong cyclone over vitually the same place and about the same i the forecast run.

I believe that the GFS run is too strong. A 961 hpa bomb cyclone in June would be somewhat lower than the GAC back in 2012 which bottomed out at about 963-964 hpa. At this stage, the ECMWF solution seems more realistic if such a cyclone is going to develop.

In any case, the upcoming forecast runs will be very, very interesting to follow!!!

The surface air over the CAA is getting warmer everyday, and by the 20th, some parts will reach 10oC. Between that and the wave activity, the ice is gradually breaking up.Surface air for the 17th pictured Below

Let's try it again! BOTH GFS and ECMWF 12z op runs depicts a possible bomb cyclone by D8 ranging from 961 hpa (GFS) to 971 hpa (ECMWF). While it certainly is far away in time to make any clear conclusions it is absolutely a bad omen that both models evolve such a strong cyclone over vitually the same place and about the same i the forecast run.

I believe that the GFS run is too strong. A 961 hpa bomb cyclone in June would be somewhat lower than the GAC back in 2012 which bottomed out at about 963-964 hpa. At this stage, the ECMWF solution seems more realistic if such a cyclone is going to develop.

In any case, the upcoming forecast runs will be very, very interesting to follow!!!

Worth noting that GFS overestimated the depth of the low currently moving into the arctic; earlier runs had it bottoming out much lower than current runs. Will be interesting to watch, in any case.

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seaicesailor

The ACNFS drift forecast at slow motion for today and following 6 days. Interesting that the dispersion that the storm brings will not really push ice back toward the coasts in the open water areas, except for Kara. Laptev and ESS open areas gonna get bigger, even Beaufort and Chukchi it seems. Surprising given the storm but it must be that the coupling with the Beaufort high keeps the circulation in this way

Let's try it again! BOTH GFS and ECMWF 12z op runs depicts a possible bomb cyclone by D8 ranging from 961 hpa (GFS) to 971 hpa (ECMWF). While it certainly is far away in time to make any clear conclusions it is absolutely a bad omen that both models evolve such a strong cyclone over vitually the same place and about the same i the forecast run.

I believe that the GFS run is too strong. A 961 hpa bomb cyclone in June would be somewhat lower than the GAC back in 2012 which bottomed out at about 963-964 hpa. At this stage, the ECMWF solution seems more realistic if such a cyclone is going to develop.

Interestingly enough both 2 model's main runs have the Arctic cyclone in the same place in 192 hours. That's a rare agreement for +8 days ahead!! That of course does not mean it will happen.

GFS:

ECMWF:

The ensembles of ECMWF show it too there exactly. Quite an agreement.

But does such a cyclone there, this time of the year means there will more snow there(i see the cyclone is accompanied with -8 °C at 850 hPa so definitely snow and not rain), so it will help the ice to grow stronger? I know about the winds, waves etc destroying ice, but having more snow on the top of ice, isn't a greater factor so ultimately the ice is favored?

If that bomb cyclone eventuates - and its still a long way off - there will be widespread wind including in the Bering, accelerating the inflow of warm water, and Chukchi seas creating waves, as well as around the cyclone itself . It also drags very warm air in from Siberia. According to GFS 12z run

It is a long way off so unlikely to play out this way, but I posted the image because it seems remarkable for its "oceanic" windiness - a sign of things to come?

As an observer, not a climate scientist, I can only comment on the data that shows what has been, what is and what with reasonable confidence can be expected to happen (as far as weather outlook, that is looking up to 5 days ahead in summer?)..

However,- CCI-reanalyzer shows strong sea temperature anomalies in the far north Atlantic and the pacific mouth of the CAB,- CCI-reanalyzer also shows that summer has arrived in the CAB with average temperatures at and above zero for most of the CAB and surrounding Arctic,- decline in sea ice extent (Jaxa) in June means that a second lowest minimum is possible with melt from now to minimum at just above the previous 10 year average.

With just 3 months of the melting season remaining and with no signs of significant melt-accelerating conditions , a record low is looking far less possible.

Gerontocrat, without starting an off topic discussion, but what me preoccupies most this season is the extremely low PIOMAS volume measurement. Hopefully the danish data is right, but the behavior of extent and area until now rather tends to the opposite: A relatively cold, that means not spectacular melting season and a beginning July drop that could become significant in the coming days.

All in all there's still everything in the cards, maybe the graphs will follow 2012 until August, just like they did last year, before they go into another direction whichever that should be. We'll see ...

JAXA thickness map is completely out of whack at the moment and, therefore I do not recommend even bothering to glance at the volume chart. Unless you think that big glob of 5 meter thick ice is really there, and is really that mobile, because it is really moving around a lot and changing shape and morphing. To me, the ice in the area this glob is showing up in, shows signs of traction rather than compaction and ridging.

As an observer, not a climate scientist, I can only comment on the data that shows what has been, what is and what with reasonable confidence can be expected to happen (as far as weather outlook, that is looking up to 5 days ahead in summer?)..

However,- CCI-reanalyzer shows strong sea temperature anomalies in the far north Atlantic and the pacific mouth of the CAB,- CCI-reanalyzer also shows that summer has arrived in the CAB with average temperatures at and above zero for most of the CAB and surrounding Arctic,- decline in sea ice extent (Jaxa) in June means that a second lowest minimum is possible with melt from now to minimum at just above the previous 10 year average.

With just 3 months of the melting season remaining and with no signs of significant melt-accelerating conditions , a record low is looking far less possible.

it's really easy to find graphs and data that fits ones intended statement. i prefer to stick to the more reliable sources and to the truth (no sign of signifianct melt etc is not true) and to the laws of physics that cannot be fooled with photoshopped images and cherry picked statistics. energy is there, thickness and volume is low. that alone is enough to worry because the total amount of ice incicates the amount of energy needed to get rid of it which, obviously, is much less than ever before and it will have an impact.

i did not pay attention to other posts from you but there are well know sites where that post would be welcome and fit into the general pattern, just sayin'

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i call this an acceleration of melting and at or close to the lowest level

further the ice is fragmented and moblle

further the volume of the most reliable source is lowest ever

so perhaps it's the other way around when it comes to stand something ?

at least i think that of the several points i mentioned all are true which one cannot say fromthe general direction and arguments in that post, hence what's wrong to point it out?

i know that i'm not a diplomat but for me diplomacy is a synonym for hypocricy and lies and i do not have the intention to become one, i prefer a clear word and prefer to say sorry if i overshoot, still better than avoiding facts just because someone could be hurt. personal choice of course.

« Last Edit: June 17, 2017, 06:20:36 PM by magnamentis »

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As an observer, not a climate scientist, I can only comment on the data that shows what has been, what is and what with reasonable confidence can be expected to happen (as far as weather outlook, that is looking up to 5 days ahead in summer?)..

However,- CCI-reanalyzer shows strong sea temperature anomalies in the far north Atlantic and the pacific mouth of the CAB,- CCI-reanalyzer also shows that summer has arrived in the CAB with average temperatures at and above zero for most of the CAB and surrounding Arctic,- decline in sea ice extent (Jaxa) in June means that a second lowest minimum is possible with melt from now to minimum at just above the previous 10 year average.

With just 3 months of the melting season remaining and with no signs of significant melt-accelerating conditions , a record low is looking far less possible.

it's really easy to find graphs and data that fits ones intended statement. i prefer to stick to the more reliable sources and to the truth (no sign of signifianct melt etc is not true) and to the laws of physics that cannot be fooled with photoshopped images and cherry picked statistics. energy is there, thickness and volume is low. that alone is enough to worry because the total amount of ice incicates the amount of energy needed to get rid of it which, obviously, is much less than ever before and it will have an impact.

i did not pay attention to other posts from you but there are well know sites where that post would be welcome and fit into the general pattern, just sayin'

As you may or may not have noticed, I said that despite a coolish arctic so far, a second lowest minimum is eminently possible. Such a result when melting conditions are not that favourable would be very significant.It is obvious as I have posted many times, that volume reduction cannot exceed extent reduction indefinitely. I merely suggest that the massive extent reduction that must happen is not going to happen this year. This is a surprise after tbe winter events.

ps : I do not change my data sources according to the result I seek to achieve. This has pissed off many of my employers.I am not competent to judge the reliability of this data, except that it is produced by dedicated climate science professionals.pps: Goodbye.

JAXA SIE is about 50k from 2012 numbers per date. NSIDC SIE has been running ahead of 2012. I know that does not mean that this will be a record year without doubt, but why does everyone keep using extent numbers, as if extent is dropping that slowly. It has not been that slow.

Yeah romett, with the significant size and duration of the wind field, it's hammer time for a large area – covering Laptev, part of ESS and extending well into the CAB. In less than 30hrs Null School has 2.2 meter waves forming at the edge of where its coverage ends.

Of course, in addition to other impacts, this event will yield significant upwelling and halocline-mixing. Given the current state of the pack (of the large area in question), perhaps someone with more experience would like to chime in about the degree of upwelling/mixing, and about how it might effect the pack during & after the cyclone?

Edit: I included a snapshot of the wind field in 30 hrs (highest winds 50km at sampling point). I'd encourage those interested to go to null school or Windytv(ECMWF setting) and check things out as i don't have time to do animations. This thing is big!

Cryosat thickness reports are stopped for the summer because melting interferes with measuring thickness by satellite. JAXA keeps on reporting thickness through the summer but the measurements are affected by the same problems as Cryosat.

JAXA thickness maps are unreliable during melt season and should not be used to make statements about the progression of the 2017 melt season.

As a general rule cyclones in June are good for ice preservation. If the cyclones coming over the next week or two disrupt the flow of ice towards the Fram strait it will slow down the drop in sea ice extent. There is hope that we won't see a disastrous drop in extent, but forecasts beyond a week out of low versus high pressure in the Arctic are pretty much worthless this time of year. We'll see what happens.